This invention pertains to a measuring rafter gauge which will locate the pitch of any roof and which will locate the length of the common, hip and valley rafter along with the position and angle of the seat cut and is self-squaring.
Previous inventions in this area have not been able to perform all six functions with a single device. U.S. Pat. No. 1,683,438, roof framing rule, provides various rules for the location and positioning of various rafters, but it does not measure the length in a single operation, requiring the repositioning of the rule several times along the length of the rafter to be cut and, in addition, requires the use of a book of tables to convert the measurement into the proper angle.
There are other tools which are used from the ground to provide the pitch but are not able to provide the length of the rafter or the position of the seat cut. The squangle, U.S. Pat. No. 3,289,301, allows the pitch to be obtained from the ground. Of course, even a sextant could perform this operation. But neither instrument will provide the length of the rafters or the position of the seat cut.
While there have been various rafter books and tables produced, these books have not been recently published. Generally, today's carpenters are not well versed in the use of rafter books and tables. Consequently, common, hip and valley rafters leave much to be desired.